1. Field of the Invention
The present invention relates generally to a cleaner for treating a surface. More particularly, the present invention relates to such a cleaner which removes graffiti from certain desired protective coated or painted surfaces without damage to that protective coat and without altering the surface. In untreated surfaces, such a cleaner shall remove unwanted paint and graffiti without damage to the surface. Further, such a cleaner has been found to be effective in cleaning and removing paint and finish from furniture.
In recent years there has been an increased concern over the rapidly growing problem of graffiti, particularly in urban areas. In modern times, the term graffiti has come to acquire a meaning which differs substantially from it's historical meaning. The modern observer views graffiti not as an art form, but rather, as a form of destruction and vandalism.
The application of graffiti and other unwanted paint or coatings on a surface has become most prevalent in institutions, such as, schools, public and private buildings, automobiles, trucks, train cars and rest rooms which are available to the public at large. Graffiti is even more problematic in open areas, such as, support walls and piers, bridges, retaining walls, sound barriers, the exterior walls of buildings, various structures in parks, which incidentally were put there in the first place to cosmetically improve the parks and the like. The vast majority of such graffiti are color markers having pigmented dyes with fast drying, penetrating solvents and oil based paints including enamels, epoxies, lacquers and urethanes. The graffiti is usually applied by spray cans, and is applied to various types of surfaces.
2. Description of the Prior Art
The methods for the removal of graffiti and unwanted paint, which for the most part are cost prohibitive, have heretofore included sandblasting, hydrosanding and hydroblasting the surfaces on which the graffiti appears. These methods often involve a subsequent re-painting of the surface to restore its aesthetically pleasing appearance since sandblasting, hydrosanding and hydroblasting make a surface porous and rough. Depending on the nature of the surface, such methods could have a potentially deleterious effect to the surface. For example, such methods can etch or score the surface thereby creating a degree of porosity which assists in holding later applied graffiti to the surface, as well as to any area in close proximity, and sandblasting will emit potentially carcinogenic and siliceous particles into the air.
Another method which has been used for removal of graffiti and unwanted paint includes chemical treatment of the surface on which the graffiti appears, such as acids and caustic solutions. This method has proven costly and unsuccessful. It has been found that repetitive chemical cleaning treatment quickly destroys the painted surface thereby necessitating frequent repainting. The application of such strong chemical cleaners also has a deleterious effect to the surrounding environment and on the person applying the chemicals. Further, some of the chemicals are now either banned as pollutants to the environment or, perhaps, in the process of being banned.
Perhaps the most common way of removing graffiti is to repaint the surface and hope that the same individuals who had applied the original graffiti do not take the repainting as a new invitation to refine their art skills. As can be appreciated, this approach is perhaps the least effective. It requires the use of a paint which is capable of covering the graffiti without bleed through of the underlying graffiti.
U.S. Pat. No. 4,716,056, which issued on Dec. 29, 1987 to Frank Fox and Cassius W. Leys, the latter being the inventor of the present invention, relates to a system for treating a surface and discusses therein non-toxic cleaners which are particularly adaptable for removal of graffiti. A particularly preferred cleaner set forth in this patent comprises: 28% toluene, 10% methyl ethyl ketone, 13% xylene, 2% ethylene glycol n-butyl ether, 10% methylene chloride, 15% propane, 15% isopropanol, 2% methanol and 5% o-dichlorobenzene. The drawbacks of this formula is that the methylene chloride lifts the paint off in large scabs instead of emulsifying the paint into a water soluble emulsion as in the present invention. Further, methylene chloride leaves a residue on the surface to be cleaned. Methylene chloride, furthermore, has been banned in some states due to its toxicity and has been classified as a hazardous chemical by the Occupational Safety and Health Administration (O.S.H.A.) and the Environmental Protection Agency (E.P.A.).
Other cleaners, such as AGP Wipe-Away by AGP Systems, Inc., the assignee of the present application, remove graffiti, but do not act as effectively and with the very low volatile organic compounds (V.O.C.) as the cleaner of the present invention. Further such cleaners are not water soluble, biodegradable and non-flammable.